Magnitude 6.3 earthquake jolts Tokyo

TOKYO - A strong earthquake with a preliminary magnitude of 6.3 has jolted in Tokyo and its environs.

Japan's Meteorological Agency said the quake struck at 8:08 a.m. local time Tuesday. The epicenter of the quake was located just off the coast of Chiba, east of Tokyo.

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There were no initial reports of injuries or damage in the prefecture. No tsunami warning was issued.

The agency said the quake was a string of strong aftershocks since the 9.0-magnitute earthquake and ensuing tsunami in northeastern Japan on March 11. The twin disasters decimated much of the region, killing up to 25,000 people and setting off radiation leaks at a coastal nuclear plant by knocking out its cooling systems.